The invention relates to a device for separating a harvested stream, a cleaning system including such a separation device, and a harvesting machine including such a cleaning system.
The invention applies to the field of mechanised harvesting of fruit growing on trees or bushes, such as grapes, berries, coffee berries, olives and other fruit, in particular growing in bunches.
The fruit is conventionally harvested by a shaker system that straddles a row of plants to detach the harvest. The harvested crop stream obtained is then conveyed into the machine to be stored in at least one hopper provided for this purpose or in a trailer driven by.
However, because of the action of the shaker system, the harvested crop stream includes, in addition to detached fruit, and among other things, juice, leaves, wood particles, bunches of fruit of various sizes. To eliminate components other than fruit, in particular leaves and wood particles, harvesting machines include a cleaning system which is adapted to eliminate said components from the stream by suction before storage.
In particular, an aspiration or suction device can be disposed above the conveyor transporting the harvested stream from the shaker system to the storage facility. However, the problem then arises of adjusting the suction force to remove from the stream as many components without fruit as possible, and to do this without eliminating the harvested fruit and juice.
To solve this problem it has been proposed to equip these machines with a device for separating the harvested stream into two layers, respectively a top layer containing components of greater size, especially components other than fruit, and a bottom layer containing detached pieces of fruit and juice. Accordingly, as the suction device faces the top layer, the probability of sucking up components from the bottom layer is reduced.
Patent applications EP-1 192 850 and EP-1 336 333 propose to effect this separation by means of a conveyor equipped with elongate members that are fixed at the upstream end with an intermediate spacing allowing components of the bottom layer to pass between them. Accordingly, separation is effected by feeding the harvested stream upstream of said elongate members, then displacing said stream along the members over a sufficient length to complete said separation, and then ejecting the top and bottom layers in the downstream portion above which the suction device is placed.
In this arrangement the separation members on the machine are subjected to mechanical loads during harvesting, especially vibratory loads. Accordingly, the downstream ends of the members being free, the problem arises of holding said members in position to maintain a spacing between them that is adapted to retain the components of the top layer.
This problem is all the more critical in the case of a small harvesting machine in which the space available prevents the incorporation of a separator device, said device being fed by two conveyors coming from the shaker system. To complete separation, it is then necessary to use longer members, which increases the risk of relative displacement thereof.
The invention aims to improve on the prior art by in particular proposing a separator device including lengthwise separator members that are fixed to guarantee that their spacing is maintained under mechanical loads, this being achieved without forming any obstacle to the harvested stream transported by said device.